The invention relates to a receiving element useful, for example, as a centering pin or receiving pin for centering and receiving components, in particular a plurality of metal sheet parts or at least one metal sheet part having a threaded female element, and more particularly employable in association with welding tools, in particular pressure welding tools, apparatus or machines.
A receiving element is disclosed in WO 2004/069 468 A1, having a bolt that, in the area of its external surface, which is largely parallel to a longitudinal axis, includes at least two recesses with apertures. Arranged in these recesses are pins that comprise or contain wear-resistant material and that extend somewhat radially through said apertures and project over the external surface with a predefined overhang. Such receiving elements can be introduced into bores of at least one component for fixing and/or aligning for subsequent machining. For instance, if two metal sheets are to be joined to one another by welding, these contain receiving bores that match one another and into which a receiving element of the type cited is subsequently introduced for centering and receiving the metal sheets. Particularly in the case of large components, a plurality of such receiving elements are usefully provided as production or assembly aids. The receiving elements can also be employed as holding pins and/or guide pins in machines, systems, or machining systems for components, these being for instance automatic welding machines, punches, or presses. Production of these previously known receiving elements requires a certain complexity because first the at least two lateral apertures must be added to the bolt, which normally comprises metal, and then the at least two pins, which comprise or contain sintered material, must be introduced into the apertures, whereby in a useful manner in a further machining step, the pins projecting outward from the bolt are machined such that the surface areas of the pins that overhang farthest radially are located on a common surface. Even without performing this latter method step, adding at least two apertures to the bolt and preparing and inserting the two aforesaid pins entails production complexity that is not insubstantial.
Moreover, a receiving element is disclosed in JP 02 290 696 A that has a sleeve comprising a sintered material, through which a bolt, provided with a tip, passes. The end of the bolt facing away from the tip is provided with a thread that engages in a threaded bore of an element provided with a male thread, the aforementioned sleeve being clamped axially between the bolt tip and the element. The production of the cylindrical sleeve made of sintered material is quite complex in order to avoid radial play in terms of the bolt that passes through and conversely to avoid undesired radial compression and associated waste during production. In addition, this receiving element also comprises at least three parts, specifically sleeve and bolt and the threaded element that has a male thread, and thus the various machining steps being disadvantageous especially during serial production of large numbers of units.
Based upon the foregoing, the underlying object of the invention is to further develop a receiving element with less structural complexity while avoiding the aforesaid disadvantages such that high dimensional stability and positioning accuracy are assured for a long service life. The production of the receiving element should not require great complexity and/or material consumption, and should be economical to implement. Moreover, it should be possible without significant problem to assure the electrical insulation that is used when the receiving element is used or employed for producing a weld joint, in particular for metal sheet parts and/or one metal sheet part with threaded female elements. Furthermore, the receiving elements should especially be used in welding systems or devices, for example, for producing pressure welded joints.